Identification of c.483C>T polymorphism in the caprine tyrosinase-related protein 1 (TYRP1) gene

Abstract

Tyrosinase-related protein 1 (TYRP1) has been shown to play a fundamental role in pigmentation both in human and mouse. In this work, we aimed to characterize the variability of the caprine TYRP1 gene and investigate its segregation in a wide array of goat breeds. By partially sequencing the coding region of the TYRP1 gene in 18 individuals from eight different breeds, we were able to identify a synonymous nucleotide substitution at exon 3 (c.483C>T). An extensive survey of Iberian and Balearic (N=175), Italian (N=99), Swiss (N=54), Asian (N=14), Canarian (N=92) and North African (N=117) goats with different coat colours was carried out. We found that the C-allele has a different distribution in European vs African breeds, being almost fixed in the latter. Moreover, the C-allele showed an increased frequency in white coated breeds (Girgentana, Grigia Molisana, Blanca de Rasquera and Saanen) when compared with those displaying a dark pigmentation (Cilentana Nera, Azpi Gorri and Murciano- Granadina). This could be due to genetic drift, migration and other factors associated with the demographic history of breeds under analysis or to a genetic hitchhiking event (c.483C>T frequencies would be shaped by a neighbouring causal mutation differentially selected in white and black goats). More refined studies will be needed to distinguish between these two alternative explanations.

Keywords

• Goat, Tyrosinase-related protein 1, Coat colour